The present invention relates to devices and methods for accessing adjacent anatomical conduits with an aperture creating assembly that can be operated over a guidewire that has been initially placed between the conduits to maintain access to the connection site. The present invention further relates to the field of treatment of diseased, injured or occluded vessels or other anatomical or synthetic structures, having restricted, blocked or insufficient fluid flow, and in particular, to providing a fluid connection between neighboring vessels or other adjacently situated anatomical or synthetic structures having hollow lumens or cavities formed therein.
Restricted or blocked fluid flow in vessels or other anatomical structures, such as, for example, restricted or blocked arterial flow in coronary arteries, or other blood vessels, can result in pain, dysfunction and even death. Other vessels or structures which may experience restricted or blocked flow include blood vessels, vas deferens, fallopian tubes, intestines, lymphatic ducts, grafts, and chambers of the heart or brain.
Certain percutaneous revascularization bypass procedures have been devised wherein blood flow passageways (e.g., puncture tracts or interstitial tunnels) are formed between the lumens of adjacently situated blood vessels (e.g., between an obstructed coronary artery and an adjacent coronary vein) to bypass a diseased, injured or obstructed segment of one blood vessel. These procedures have previously been described in, for example, U.S. Pat. No. 5,830,222, assigned to the assignee of the present invention and incorporated by reference herein. Also, Provisional U.S. Patent Application Serial No. 60/010,614, also assigned to the assignee of the present invention, and incorporated herein by reference, particularly describes certain percutaneous revascularization grafting procedures devised for by-passing an obstructed artery. In these grafting procedures, a tubular graft (e.g., a segment of an endogenous blood vessel or a tube graft formed of natural or synthetic material) is adjacent or maneuvered to be adjacent to the obstructed artery. With procedures originating within the vasculature, one or more openings are formed in the graft and the adjacent artery. The openings formed in the graft are then connected to the openings formed in the artery, such that blood may flow between the graft and the artery. In these techniques, all operations are performed from within a blood vessel and generally from a remote location. For example, access to the vascular system may be gained in the groin. Long catheters are introduced from the vascular access so that a distal end of the catheter is passed through the vasculature to the by-pass site. The various cutting and vessel-to-vessel junctions are established at the by-pass site using controls operated by the surgeon at the proximal end of the catheter (i.e. at the point of access to the vascular system). In some situations, however, such percutaneous procedures are difficult, if not impossible to perform, the patient may be involved in a simultaneous surgical procedure or the clinician may prefer a surgical approach and it is desirable to effect by-passes with an open surgical procedure.
It is an object of the invention to provide new kits, devices and methods for the simplified formation of fluid passageways between adjacent portions of anatomical structures, such as blood vessels, during an open surgical procedure so that fluid flow may be provided in areas where vessels have been restricted or blocked inhibiting or eliminating fluid flow therein.
The invention is directed against the partial or complete blockages of fluid flow between anatomical structures. The invention provides over-the-wire kits, devices and methods useful in an open surgical field, for forming apertures in adjacent portions of anatomical structures such as blood vessels during a surgical procedure. The invention""s kits, devices and methods may be useful for creating alternative vascular channels to provide revascularization routes in the heart between the coronary arteries and between the cardiac veins, or in the periphery between adjacent veins, conduits and/or arteries. The kits, devices and methods of the invention may also be used to by-pass coronary arteries and to provide for cardiac venous arterialization. It will be understood by persons of ordinary skill in the art, however, that the general kits, devices and methods as described herein are equally applicable to the surgical manipulation of any anatomical structure for providing the passage of fluid flow therebetween. As used herein, the term xe2x80x9canatomical structuresxe2x80x9d or xe2x80x9cblood vesselsxe2x80x9d includes blood vessels, tubes, ducts, hollow organs, brain or heart chambers, grafts and synthetic structures.
In one aspect, the invention provides an over-the-wire kit for forming apertures in adjacent portions of a first blood vessel and a second blood vessel during a surgical procedure. The kit includes at least a first guidewire for introduction into a lumen of the first vessel to an initial cutpoint, and then through adjacent portions of sidewalls of the first vessel and the second vessel into a lumen of the second vessel. As used herein, the phrase xe2x80x9cinitial cutpointxe2x80x9d refers to a position on the sidewall of the first vessel at which it is desired to establish a passage therethrough leading to the second vessel. The guidewire is preferably introduced in an open surgical field, such as pursuant to a conventional open chest procedure. The point at which the wire is introduced into the lumen of the first vessel may be near (or opposite) the initial cutpoint. Alternatively, that point of introduction may be a distance along the vessel from the initial cutpoint.
The kit also includes a wire guided aperture creating apparatus. The aperture creating apparatus is adapted to xe2x80x9cfollowxe2x80x9d the wire, typically passing initially through a sidewall of a first vessel, through the lumen of that vessel to the initial cutpoint in the sidewall of the first vessel and then through the sidewalls of the first and second vessels, establishing apertures in those sidewalls. In one form, the aperture creating apparatus includes a first elongated element extending along a first axis between a proximal end and a distal end. That aperture creating apparatus also includes a second elongated element extending along a second axis between a proximal end and a distal end. The first elongated element is coupled to the second elongated element whereby the first axis substantially intersects the second axis at a common intersection point spaced apart from the distal ends of the elongated elements. The distal end of the first elongated element is movable with respect to the distal end of the second elongated element about an axis orthogonal to the first axis and the second axis. A tissue cutting assembly is disposed between the first and second elongated elements. At least one of the first and second elongated elements includes a passage-defining element permitting passage therethrough of the first guidewire. In an alternate form, the kit includes a second guidewire, and the second elongated element also includes a passage-defining element, permitting passage therethrough of the second guidewire.
In one form, the cutting assembly is scissors-like, with the first and second elongated elements being rigid, and being pivotally joined at a common intermediate point, to form pivoting, opposed scissors-like blades on one side of the intermediate point and to form handles on the other side. At least one of the blades includes a channel for the first guidewire to pass through. The edges of the opposed elongated elements provide the tissue cutting assembly, as in a conventional scissors.
In another form of the invention, the wire guided aperture creating apparatus may be formed from a flexible catheter with a bifurcated distal end, forming two opposed jaw-like elongated elements which are moveable in opposite directions about an axis transverse to the catheter at the point of bifurcation. The elongated elements may be flexible or rigid at least near their distal ends. In this form, the one (or both, in two-wire configurations) elongated elements has a passage extending therethrough for passing over a guidewire. A tissue cutting assembly is disposed between the elongated elements.
In various forms of the invention, and by way of example, the tissue cutting assembly may include a blade positioned at the point of intersection or bifurcation, pointing away therefrom. Alternatively, one of the elongated elements may house a longitudinally extending blade and the other element may house an anvil, which when the elongated elements are moved toward each other, can effect cutting of tissue therebetween. Alternatively, a laser cutter, or radio frequency (rf) cutter or hole punch (with anvil) may be positioned between the opposing elongated elements.
In the method of the invention, a one (or two) wire kit of the above described form is used. Initially, in an open surgical field, a lead end of first guidewire is passed through a veinotomy in a vein (the first blood vessel) and into its lumen. The lead end of the first guidewire is then advanced through the lumen until reaching a desired point (referred to as the initial cutpoint) of a junction between the first blood vessel and an adjacent artery (the second blood vessel). The lead end is then passed through the adjacent sidewalls of the first and second vessels and into the lumen of the second vessel. In a two wire procedure, a second guidewire is passed through the veinotomy and into the lumen of the first blood vessel and as advanced so that its lead end is disposed within that lumen but extends beyond the initial cutpoint.
Following insertion of the guidewire(s), the path defining element of the first elongated element of the guided wire aperture creating apparatus is passed over the first guidewire, and the distal ends of the elongated elements are fed through the veinotomy into the lumen of the first blood vessel. The wire guided aperture creating apparatus is advanced in that lumen, with the first elongated element tracking the first guidewire. Upon reaching the initial cutpoint, the first elongated element is led (by the first guidewire) from the lumen of the first blood vessel to the lumen of the second blood vessel, with the second elongated elements remaining in the lumen of the first blood vessel. In two wire procedures, the second elongated element is fed over the second guidewire at the same time that the first elongated element is fed over the first guidewire. Then, as the wire guided aperture creating apparatus is advanced just beyond the initial cutpoint, the first elongated element follows the first guidewire to the lumen of the second blood vessel, and the second elongated element affirmatively follows the second guidewire to continue in the lumen of the first blood vessel.
With the wire guided aperture creating apparatus so positioned just beyond the initial cutpoint, the tissue cutting assembly is then operated to cut tissue between the first and second elongated elements (i.e., simultaneously, the walls of the first and second blood vessels). In the scissors-like forms of the invention, handles can be operated to drive the blades to cut the tissue. In the other forms, the various aperture creating assemblies are operative to cut the tissue between the first and second elongated elements. For example, where there is an outwardly facing blade at the intersection or bifurcation point, the wire guided aperture creating apparatus need only be advanced so that the blade effects the cutting. For example, a laser or rf source near the distal end of one of the elongated elements might be actuated to ablate tissue between the elongated elements. Alternatively, the elongated elements may be driven toward each other so that a blade or punch on one elongated element cuts tissue between it and an anvil on the other elongated element. Following the effecting of a desired length cut, the wire guided aperture creating apparatus is withdrawn from the blood vessels and the adjacent vessels may be further joined, if necessary. A scaffolding device, or other treatment may be provided to the aperture site for the purpose of maintaining fluid flow.
In another form of the invention, the aperture creating apparatus is adapted to follow the guidewire, following introduction of that wire into the lumen of the first vessel and positioning that wire to the initial cutpoint and through the sidewalls of the first and second vessels and into the lumen of the second vessel. As the lead end of the aperture creating apparatus follows (i.e., is guided by) the wire and passes through the sidewalls of the first and second vessels, a tissue cutting, tissue removing, tissue ablating or tissue enlarging assembly cuts, removes, ablates or enlarges, the portions of those sidewalls adjacent to the guidewire, establishing a passageway connecting the lumens of the first and second vessels.
The aperture creating apparatus in this form is a rigid or flexible catheter-like structure that is fed over the guidewire, having a tissue cutting, tissue removing, tissue ablating or tissue enlarging element at its lead end. In various forms of the invention, the tissue cutting, tissue removing, tissue ablating or tissue enlarging element can vary. For example, that element may include a remote actuated inflatable balloon (concentric or eccentric with respect to the axis of the catheter) at or near its distal tip, or may include a remotely retractable or fixed cutting blade (or blades) at or near the catheter distal tip, or may include a remote actuated rf ablation electrode (concentric or eccentric) at or near the catheter distal tip, or may include a laser at or near the catheter tip. An orientation marker may be included on devices having eccentric placement of the aperture creating assembly relative to the body of the elongated element. The elongated element may include a implantable scaffolding device which can be used to create the aperture and can be left permanently implanted to scaffold the aperture sites. Furthermore, a hemostasis apparatus may be included the passage defining element, or guidewire lumen, to prevent leakage of blood through the lumen.
The invention also is a kit including a guidewire and the latter-described aperture creating apparatus.